Blended fuel composition having improved cold flow properties

ABSTRACT

There is provided a fuel composition comprising petroleum based component and a renewable based component, wherein at least 20% of the compounds in said petroleum based component having boiling point range equal or greater than the boiling point of said renewable based component.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a non-provisional application which claims benefitunder 35 USC §119(e) to U.S. Provisional Application Ser. No. 61/265,076filed Nov. 30, 2009, entitled “A BLENDED FUEL COMPOSITION HAVINGIMPROVED COLD FLOW PROPERTIES” which is incorporated herein in theirentirety.

STATEMENT OF FEDERALLY SPONSORED RESEARCH

None

FIELD OF THE DISCLOSURE

The present invention relates generally to fuel compositions. Morespecifically, the present invention relates to a blended fuelcomposition comprising petroleum based fuel and renewable fuel whichexhibit improved cold flow properties. The present invention alsorelates to the method of making such compositions.

BACKGROUND OF THE DISCLOSURE

There is a national interest in the discovery of alternative sources offuels and chemicals, other than from petroleum resources. As the publicdiscussion concerning the availability of petroleum resources and theneed for alternative sources continues, government mandates will requirefuel range hydrocarbons to include, at least in part, hydrocarbonsderived from sources besides petroleum. As such, there is a need todevelop alternative sources for hydrocarbons useful for producing fuelsand chemicals.

One possible alternative source of hydrocarbons for producing fuels andchemicals is the natural carbon found in plants and animals, such as forexample, oils and fats. These so-called “natural” carbon resources (orrenewable hydrocarbons) are widely available, and remain a targetalternative source for the production of hydrocarbons. For example, itis known that oils and fats have been successfully hydrotreated toproduce hydrocarbons/fuel range hydrocarbons which is also called“Renewable fuel” such as renewable diesel fuels.

Renewable diesel fuels are gaining greater market acceptance as a cutterstock to extend petroleum diesel market capacity. The blends ofrenewable diesel fuels with petroleum diesel are being used as fuel fordiesel engines, utilized for heating, power generation, and forlocomotion with ships, boats, as well as motor vehicles.

It is know to those skilled in the art that the renewable diesel may beprepared by reacting vegetable oils and/or animal fats with ahydrogenation and deoxygenation catalyst at the hydrogenation anddeoxygenation conditions.

The main components in renewable diesel are n-C15 to n-C18 paraffins.Therefore, renewable diesel exhibits poor cold flow properties, e.g.,cloud point, pour point and Cold Filter Plugging Point (CFPP).Generally, it is thought that renewable diesel would have a big impacton the cold flow properties of petroleum diesel, which would limit itsblending concentration in the diesel pool.

The cold flow properties of renewable diesel can be improved by usingdewaxing technology, either cracking or isomerization, to lower the coldflow properties, thereby minimizing the impact of renewable diesel onthe cold flow properties of petroleum diesel. However, such processeswill increase the production cost and decrease the diesel volume yield.

In addition, the cold flow properties of renewable diesel can also beimproved by adding cold flow additives. However, cold flow additives areexpensive. With the implementation of renewable diesel, the use of coldflow additives is expected to increase. Therefore, using cold flowadditive is economically unfavorable.

As such, development of a blended fuel composition having improved coldflow properties without the above economic concerns would be asignificant contribution to the art and to the economy.

BRIEF DESCRIPTION OF THE DISCLOSURE

The present invention relates generally to fuel compositions. Morespecifically, the present invention relates to a blended fuelcomposition comprising petroleum based fuel and renewable based fuelwhich exhibit improved cold flow properties.

In one embodiment of the present invention, there is provided acomposition comprising a petroleum based component and a renewable basedcomponent, wherein at least 20% of the compounds in the petroleum basedcomponent having boiling point range equal or greater than the boilingpoint of the renewable based component. The amount of the renewablebased component is in the range between 0.1 vol. % to 50 vol. %, basedon the total volume of the fuel composition.

The renewable based component comprises hydrocarbons that are derivedfrom natural, replenishable feed stock which can be utilized as sourceof energy.

The petroleum based component comprises hydrocarbons derived frompetroleum refining process. The petroleum based component can be adiesel base fuel having boiling points within the range of 150° C. to400° C.

In one embodiment of the present invention, a method is provided forpreparing a fuel composition comprising blending a petroleum based fueland a renewable based fuel, wherein at least 20% of the compounds in thepetroleum based component having boiling point range equal or greaterthan the boiling point of the renewable based component.

It is discovered in this invention that the impact of renewable fuel onthe cold flow properties of petroleum fuel depends on the boiling pointrange of the petroleum based fuel. This invention enables the refineryto minimize the use of cold flow additives when they implement renewablediesel technology.

Other objects, advantages and embodiments of the invention will beapparent from the following detailed description of the invention andthe appended claims.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

The present invention relates generally to fuel compositions. Morespecifically, the present invention relates to a blended fuelcomposition comprising petroleum based fuel and renewable based fuelwhich exhibit improved cold flow properties. The present invention alsorelates to the method of making such compositions.

According to one embodiment of the current invention, there is provideda fuel composition comprising petroleum based component and a renewablebased component, wherein at least 20% of the compounds in said petroleumbased component having boiling point range equal or greater than theboiling point of said renewable based component.

According to yet another embodiment of the present invention, there isprovided a process for preparing a fuel composition comprising blendinga petroleum based fuel and a renewable based fuel, wherein at least 20%of the compounds in the petroleum based component having boiling pointrange equal or greater than the boiling point of the renewable basedcomponent.

According to the various embodiment of the present invention, thepetroleum based component is a hydrocarbon derived from petroleumrefining process. Petroleum based fuel refers to a fuel that includes afractional distillate of petroleum. The distillate fuel in many casescan be described as a gasoline or middle distillate fuel oil.

The middle distillate fuels typically are divided into several typesfuels including: jet or turbine fuels, automotive diesel fuels, railroaddiesel fuels, and heating oils. These products are blended from avariety of refinery streams to meet the desired specifications. Otherexamples of middle distillate fuel may include industrial gas oils,distillate marine fuels, kerosene fuels such as aviation fuels orheating kerosene, light and heavy cycle oils as obtained in a fluidcatalytic cracking unit, a Fisher-Tropsch derived fuel, in particular aFischer-Tropsch derived diesel fuel.

Petroleum derived gas oil may be obtained from refining and optionallyhydroprocessing crude petroleum source. It may be a single gas oilstream obtained from such a refinery process or a blend of several gasoil fractions obtained in the refinery process via different processingroutes. Examples of such gas oil fractions are straight run gas oil,atmospheric gas oil, vacuum gas oil, gas oil as obtained in a thermalcracking process, and gas oil as obtained from a hydrocracker unit.

The fuel composition to which the present invention is preferably to useis for an internal combustion engine, for example a diesel fuelcomposition which is used in an automotive diesel engine. Therefore, thepetroleum based component may be any known diesel base fuel, and it mayitself comprise a mixture of diesel fuel components. It may have asulfur content of 0 to 20,000 ppmw (parts per million by weight). It mayalso have a sulfur content of 0 to 15 ppmw.

Typical diesel fuel components comprise liquid hydrocarbon middledistillate fuel oils, for instance petroleum jet or turbine fuels,automotive diesel fuels, railroad diesel fuels, heating oils and gas oilThey will typically have boiling points within the usual diesel range of150° C. to 400° C., depending on grade and use.

Further according to various embodiments of the present invention, arenewable based component is a hydrocarbon that is derived from natural,replenishable feed stock which can be utilized as source of energy.Suitable examples of a renewable based component include, but notlimited to, bio-diesel which is a product derived from thetransesterification of a material of biological origin with an alcoholor from reacting a fatty acid with an alcohol; renewable diesel which isa product derived from hydrotreating a material of biological origin;alcohol; other oxygenate; vegetable oil or vegetable oil derivatives; abiomass pyrolysis bio-oils, or any combinations thereof. The abovementioned material of biological origin can be selected from anytriglyceride containing feedstock e.g. vegetable oils, vegetable fats,animal fats, fish oils, algae oil; any mixtures thereof.

Examples of alcohols used here include methanol, ethanol, and mixturesthereof, although virtually any C1-10 alcohol can be used.

Bio-diesel is commonly produced by the reaction of a material ofbiological origin with alcohols in the presence of a suitable catalyst.A material of biological origin is natural triglycerides derived fromplant or animal sources. The reaction of natural triglycerides with analcohol to produce a fatty acid ester and glycerin is commonly referredto as transesterification. Alternatively, bio-diesel can be produced bythe reaction of a fatty acid with an alcohol to form the fatty acidester. The fatty acid segments of triglycerides are typically composedof C10-C24 fatty acids, where the fatty acid composition can be uniformor a mixture of various chain lengths. The bio-diesel may be producedfrom single sourced components, or blends of multiple triglyceridecontaining feed stocks.

The term, “triglyceride,” is used generally to refer to any naturallyoccurring ester of a fatty acid and/or glycerol having the generalformula CH₂(OCOR₁)CH(OCOR₂)CH₂(OCOR₃), where R₁, R₂, and R₃ are the sameor different, and may vary in chain length. Vegetable oils, such as forexample, canola and soybean oils contain triglycerides with three fattyacid chains. Useful triglycerides in the present invention include, butare not limited to, triglycerides that may be converted to hydrocarbonswhen contacted under suitable reaction conditions. Examples oftriglycerides useful in the present invention include, but are notlimited to, vegetable oils including soybean and corn oil, peanut oil,sunflower seed oil, coconut oil, babassu oil, grape seed oil, poppy seedoil, almond oil, hazelnut oil, walnut oil, olive oil, avocado oil,sesame oil, tall oil, cottonseed oil, palm oil, rice bran oil, canolaoil, cocoa butter, shea butter, butyrospermum, wheat germ oil, illipsebutter, meadowfoam, seed oil, rapeseed oil, borange seed oil, linseedoil, castor oil, vernoia oil, tung oil, jojoba oil, ongokea oil,Jatropha oil, algae oil, yellow grease (for example, as those derivedfrom used cooking oils), and animal fats, such as tallow animal fat,beef fat, and milk fat, and the like and mixtures and combinationsthereof.

According to one embodiment of the present invention, a renewable basedcomponent may be a renewable diesel that is produced by hydrotreatingtriglyceride containing feedstock in the presence of a suitablecatalyst.

Useful catalyst compositions for the hydrotreating process include anycatalysts which may be effective in the conversion of triglycerides tohydrocarbons (e.g. renewable diesel) when contacted under suitablereaction conditions. Examples of suitable catalysts includehydrotreating catalysts. Examples of hydrotreating catalysts useful inone embodiment of the present invention include, but are not limited to,materials containing compounds selected from Group VI and Group VIIImetals, and their oxides and sulfides. Examples of suitable supportmaterials for the hydrogenation catalysts include, but are not limitedto, silica, silica-alumina, aluminum oxide (Al₂O₃), silica-magnesia,silica-titania and acidic zeolites of natural or synthetic origin.Examples of hydrotreating catalysts include but are not limited toalumina supported cobalt-molybdenum, nickel sulfide, nickel-tungsten,cobalt-tungsten and nickel-molybdenum. Other catalysts useful in thepresent invention are sorbent compositions. Sorbent compositions can beused in either the fixed-bed reactor or the fluidized bed reactorembodiments.

According to one embodiment of the present invention, the reaction zonemay comprise any suitable type of reactor. Exemplary reactors includefixed bed reactors and fluidized bed reactors. Generally, the reactionconditions at which the reaction zone is maintained generally include atemperature in the range of from about 260° C. to about 430° C. Inanother embodiment, the temperature is in the range of from about 300°C. to about 400° C. The reaction conditions at which the reaction zoneis maintained generally include a pressure less than about 2000 psig,and more particularly between about 100 psig to about 750 psig. In oneembodiment employing a fixed bed reactor, the pressure is maintainedbetween about 100 psig to about 350 psig. In one embodiment employing afluidized bed reactor, the pressure is maintained between about 400 psigto about 750 psig.

During the research and development efforts to evaluate cold flowproperties of petroleum fuels, renewable fuels, and their blends, it wasdiscovered that a combination of petroleum fuels with renewable fuelsresulted in an enhancement of the cold flow properties, provided atleast 20% of the compounds in the petroleum based component havingboiling point range equal or greater than the boiling point of therenewable based component.

A cold flow property of fuel is a measure of the inherent handling andthe use characteristics of a fuel at diminished temperature. The coldflow property of a given fuel is generally considered as the lowesttemperature at which the given fuel can be utilized without causingoperational difficulties. The cold flow properties of a given fuel isestimated by its cloud point (CP), pour point (PP) and its CFPP.

The CP of a fuel is the point at which first visible crystals aredetected in the fuel. The PP is a standardized term for the temperatureat which oil, for example, mineral oil, diesel fuel or hydraulic oil,stops flowing upon cooling. The Cold Filter Plugging Point (CFPP) of afuel is the temperature at and below which wax in the fuel will causesevere restrictions to flow through a filter screen. CFPP is believed tocorrelate well with vehicle operability at lower temperatures.

The invention can be practiced at high renewable based fuelconcentration, wherein the renewable based component is up to 100% byvolume of the finished fuel blend. However, in the scope of theinvention, the renewable based component is typically up to about 50% byvolume of the finished fuel blend, more typically up to about 35% byvolume of the finished fuel blend, and alternatively up to about 20% byvolume of the finished fuel blend. The invention is also applicable atrenewable based component concentrations as low as about 15, 10, and 5%by volume of the finished fuel blend, and even at very low renewablefuel concentrations as low as about 4, 3, 2, 1, and 0.5% by volume ofthe finished fuel blend.

The main components in renewable diesel are n-C15 to n-C18 paraffins.Therefore, renewable diesel exhibits poor cold flow properties, e.g.,CP, PP and CFPP. Generally, it is thought that renewable diesel wouldhave a big impact on the cold flow properties of petroleum diesel, whichwould limit its blending concentration in the diesel pool.

However, as illustrated in the following examples, it is surprising thatwhen petroleum based diesel has high percentage (e.g., >20%) ofcompounds with boiling points higher than renewable diesel, renewablediesel has little impact on the cold flow properties of petroleumdiesel. This phenomenon has been successfully demonstrated on theblended fuel composition containing up to 20% renewable based diesel. Itis therefore discovered that the impact of renewable diesel on the coldflow properties of petroleum diesels depends on the boiling point rangeof the petroleum diesels. The higher the boiling point of petroleumdiesel, the less the impact of renewable diesel on the cold flowproperties. When petroleum diesel has high percentage (e.g., >20%) ofcompounds with boiling points higher than renewable diesel (e.g. 626°F.), renewable diesel has little impact on the cold flow properties ofpetroleum diesel. When petroleum diesel has high percentage (e.g., >50%)products with boiling temperatures lower than renewable diesel (e.g.,519° F.), blending renewable diesel has a big impact on the cold flowproperties of petroleum diesel.

As a result of this discovery, the present invention is able to providea more optimized method for improving the cold flow performance of adiesel fuel composition comprising renewable based component. It has nowbeen found that by controlling the selection of the boiling point of thepetroleum based diesel, the impact of the renewable based diesel on thecold flow properties of petroleum based diesels may be minimized oreliminated.

The following examples are presented to further illustrate the presentinvention and are not to be construed as unduly limiting the scope ofthis invention.

Example 1

Table 1 shows the CP, PP, CFPP and boiling point of tallow renewablediesel. For tallow renewable diesel, ˜99% of the compounds boil below626.2° F. This is because the main components of renewable diesel aren-C 15 to n-C18 paraffins, which have boiling points between 519° F. and602° F., respectively. CP, PP and CFPP are 60° F., 54° F. and 10° C.,respectively.

TABLE 1 Cold flow Properties Tallow renewable diesel Cloud Point (F.) 60Pour Point (F.) 54 CFPP (C.) 10 SimDis Boiling Point (F.) IBP 389.1 10%BP 521.8 50% BP 580.1 80% BP 604.6 90% BP 607.7 99% BP 626.2 FBP 643.1

Example 2

Table 2 shows the impact of renewable diesel on the cold flow propertiesof diesel 1. CP, PP and CFPP all increased rapidly with renewable dieselconcentration. Boiling point of diesel 1 is shown in Table 3. Comparedto renewable diesel, boiling point of diesel 1 is low. For example, 50%of the compounds in diesel 1 is lighter than tallow renewable diesel andless than 5% is heavier than renewable diesel. Therefore, blendingrenewable diesel has a big impact on cold flow properties of petroleumdiesel.

TABLE 2 Impact of renewable diesel on the cold flow properties of diesel1 Renewable Diesel Content (%) 0 2 5 10 20 Cloud Point (F.) −6 −3 1 6 17Pour Point (F.) −21 −15 −9 −3 9 CFPP (C.) −22 −20 −18 −16 −13

TABLE 3 Boiling point of diesel 1 Boiling Point (F.) IBP 292.2 10% BP399.2 50% BP 506.2 80% BP 570.3 90% BP 598.9 99% BP 647.5 FBP 654.1

Example 3

Table 4 shows the impact of renewable diesel on the cold flow propertiesof diesel 2. CP, PP and CFPP all increased with renewable dieselconcentration. However, the impact of renewable diesel on the cold flowproperties of diesel 2 is smaller than that of diesel 1. Boiling pointof diesel 2 is shown in Table 5. Compared to renewable diesel, theboiling point of diesel 2 is still low. For example, ˜45% of thecompounds in diesel 2 are lighter than tallow renewable diesel and ˜10%is heavier than renewable diesel. Therefore, blending renewable dieselstill has impact on cold flow properties of petroleum diesel. However,since the boiling point of diesel 2 is higher than that of diesel 1, theimpact of renewable diesel on the cold flow properties of diesel 2 issmaller than that of diesel 1.

TABLE 4 Impact of renewable diesel on the cold flow properties of diesel2 Renewable Diesel Content (%) 0 2 5 10 20 Cloud Point (F.) 4 5 7 10 17Pour Point (F.) −12 −9 −3 0 9 CFPP (C.) −16 −16 −16 −16 −13

TABLE 5 Boiling point of diesel 2 Boiling Point (F.) IBP 243.0 10% BP438.7 50% BP 531.4 80% BP 602.4 90% BP 633.9 99% BP 706.6 FBP 742.8

Example 4

Table 6 shows the impact of renewable diesel on the cold flow propertiesof diesel 3. Renewable diesel has little impact on the cold flowproperties of petroleum diesel up to 20 volume %. Boiling point ofdiesel 3 is shown in Table 7. There are ˜20% of the compounds in diesel3 heavier than renewable diesel. Therefore, the heavy components indiesel 3 control the cold flow properties of the renewablediesel/petroleum diesel blends. Blending renewable diesel up to 20volume % has little impact on the cold flow properties of petroleumdiesel.

TABLE 6 Impact of renewable diesel on the cold flow properties of diesel3 Renewable Diesel Content (%) 0 2 5 10 20 Cloud Point (F.) 25 23 23 2225 Pour Point (F.) 15 15 12 15 18 CFPP (C.) −6 −7 −7 −7 −9

TABLE 7 Boiling point of diesel 3 Boiling Point (F.) IBP 247.1 10% BP415.2 50% BP 537.6 80% BP 627.8 90% BP 673.7 99% BP 744.4 FBP 757.7

It is therefore discovered that the impact of renewable diesel on thecold flow properties of petroleum diesels depends on the boiling pointrange of the petroleum diesels. The higher the boiling point ofpetroleum diesel, the less the impact of renewable diesel on the coldflow properties. When petroleum diesel has high percentage (e.g., >20%)of compounds with boiling points higher than renewable diesel (e.g. 626°F.), renewable diesel has little impact on the cold flow properties ofpetroleum diesel. When petroleum diesel has high percentage (e.g., >50%)products with boiling temperatures lower than renewable diesel (e.g.,519° F.), blending renewable diesel has a big impact on the cold flowproperties of petroleum diesel.

The results shown in the above examples, clearly demonstrate that thepresent invention is well adapted to carry out the objects and attainthe ends and advantages mentioned as well as those inherent therein.Reasonable variations, modifications and adaptations may be made withinthe scope of this disclosure and the appended claims without departingfrom the scope of the invention. While this invention has been describedin detail for the purpose of illustration, it should not be construed aslimited thereby but intended to cover all changes and modificationswithin the spirit and scope thereof.

1. A fuel composition comprising petroleum based component and arenewable based component, wherein at least 20% of the compounds in saidpetroleum based component having boiling point range equal or greaterthan the boiling point of said renewable based component.
 2. The fuelcomposition of claim 1, wherein the amount of said renewable basedcomponent is in the range between 0.1 vol. % to 50 vol. %, based on thetotal volume of the fuel composition.
 3. The fuel composition of claim1, wherein the amount of said renewable based component is in the rangebetween 0.1 vol. % to 35 vol. %, based on the total volume of the fuelcomposition.
 4. The fuel composition of claim 1, wherein the amount ofsaid renewable based component is in the range between 0.1 vol. % to 20vol. %, based on the total volume of the fuel composition.
 5. The fuelcomposition of claim 1, wherein said renewable based component comprisesisoparaffins.
 6. The fuel composition of claim 1, wherein said renewablebased component comprises normal paraffins.
 7. The fuel composition ofclaim 1, wherein said renewable based component comprises hydrocarbonsthat are derived from natural, replenishable feed stock which can beutilized as source of energy.
 8. The fuel composition of claim 1,wherein said renewable based component is selected from the groupconsisting of a product derived from hydrotreating a material ofbiological origin, a product derived from the transesterification of amaterial of biological origin with an alcohol, a product derived fromreacting a fatty acid with an alcohol, a biomass pyrolysis bio-oils, abiologically-derived oils, alcohol; other oxygenate; vegetable oil orvegetable oil derivatives, and any combinations thereof.
 9. The fuelcomposition of claim 8, wherein said material of biological origin isselected from the group consisting of vegetable oils, vegetable fats,animal fats, fish oils, algae oil, and any mixtures thereof.
 10. Thefuel composition of claim 1, wherein said renewable based componentcomprises a renewable diesel produced by hydrotreating triglyceridecontaining feedstock in the presence of a catalyst.
 11. The fuelcomposition of claim 1, wherein said petroleum based component comprisesa hydrocarbon derived from petroleum refining process.
 12. The fuelcomposition of claim 1, wherein said petroleum based fuel comprises afractional distillate of petroleum.
 13. The composition of claim 1,wherein said petroleum based component is selected from the groupconsisting of a middle distillate fuel, a jet or turbine fuel,automotive diesel fuels, railroad diesel fuels, heating oils, industrialgas oils, distillate marine fuels, kerosene fuels, light and heavy cycleoils, Fischer-Tropsch fuel, and any mixture thereof.
 14. The compositionof claim 1, wherein said petroleum based component comprises diesel basefuel having boiling points within the range of 150° C. to 400° C.
 15. Amethod for preparing a fuel composition comprising blending petroleumbased fuel and a renewable based fuel, wherein at least 20% of thecompounds in said petroleum based component having boiling point rangeequal or greater than the boiling point of said renewable basedcomponent.